Sony F828 and Shallow Depth of Field

[Jonathan Wienke]

If all you want is maximum aperture, there's zero benefit to adding additional ND once you've reached f/2 or whatever your fastest aperture happens to be and an acceptable shutter speed.

[Jonathan Wienke]

Fair enough. all I'm saying is don't go overboard to the point where you're at maximum aperture (f/2 or whatever) and you want to raise the ISO to get a faster shutter speed. Use only enough ND to get a "wide enough" aperture and "slow enough" shutter speed at minimum ISO, but no more than that.

[howard smith]

You can use both an ND and a polorizer.

[dwdallam]

Yes. ND, polarizer, or a combination of both until you get to f/2.2 and a slow enough shutter speed at ISO 64, then leave well enough alone.

Yep that makes perfect sense now. USe the filtrers to get down to F2.2, and then adjust the shutter speed as long as I need, or just before I get overexposure.

You know, the deep DoF of these types of cameras, and the nice quality of the Sony itself makes this a LOT better camera.

On a side note, I've heard rumors that Sony may be getting ready to offer an 828 type of camera without the consumer bloat, such as the movie function and other useless crap (microphone, etc.) that the prosumer F828 comes with. If they can do that while keeping the ergonomics of the camera and lens, while offering a true "through the lens option" that would be a showstopper I would think. Sony hasn't offered a new camera to replace the F828 and it's their past due. It will be interesting to see if they enter the DSLR world.

[dwdallam]

Well, I've noticed that the boards have slowed down since the last time I wrote, which was sometimes back a few moths ago. I guess you are all outside photograping!

One topic we were discussion was smaller ccd's problem of really deep depth of field, which doesn't allow very effective background blurring. This isn't too much of a problem when doing macro photography as the DoF becomes fairly shallow, even with teh Sony F828.

The problem was shooting images that were not macro, such as portraits or objects at some distance. In that case, as you all know, the smaller ccd cameras just can't produce that Shallow DoF.

Someone mentioned using a netral density filter, but no one picked up on it and I didn't really think much about it until now. I finally bought a Kenco (Hoya) polarizing filter which has about a 1 2/3 F-stop effect. Today I used the filter for the first time, and the effect was astonishing, but not for the polarizing effect.

I took two pictures or a water fountain at about 6-8 feet, one with the polarizer filter and one w/o. The difference in the blurring effect of the background was about, to my eye, maybe double, or a tad more.

The setting on the camera I used was simply to leave it in Program mode and let it find it's own light settings. I used the center weighted focus, and it was in bright sunlight at about 5PM, no clouds, at 90 degrees from the sun.

If anyone wants to see the pictures, I can post them if you request.

I'm going to test the filter to see if it will also help me get longer shutter speeds to blur water falls and other things of that sort (e.g., jugglers in daylight, and water falls that may be in a shady area.) Do you think that the filter will work in the shady area to get longer shutter speeds with this camera, or will it be too underexposed or artifacted from heat, since I'll be able to leave the shutter open longer without blowing out the highlights?

Last, am I thinking in wrong terms here by trying to use a polarizer  as a nuetral density filter? How many stops can I go to get longer shutter speeds without running into other problems? I'm prepared to buy a couple of neutral density filters if you all think it would work at least in some situations.

[dwdallam]

If all you want is maximum aperture, there's zero benefit to adding additional ND once you've reached f/2 or whatever your fastest aperture happens to be and an acceptable shutter speed.

Well, what I was hoping to do is cut some light out so I can use a slower shutter speed without washing out the highlights. The F828 only goes to F8, althugh the shutter will go to 30 seconds. So I can't shut the light down far enough in sunny situations to use a really slow shutter speed. But all this is pretty new to me, so I may have some terminology wrong here.

I was really pleased with the shallower DoF using the polarizer though. I think what happened was that the camera, to conpensate for the missing light the polarizer imposed on it, opened the aperture more, and that helped to blur the background more. So that is or seems to be another benifit of using a light cutting filter--I can opent eh apeture mroe in daylight situations and get more blurry backgrounds.

[dwdallam]

Fair enough. all I'm saying is don't go overboard to the point where you're at maximum aperture (f/2 or whatever) and you want to raise the ISO to get a faster shutter speed. Use only enough ND to get a "wide enough" aperture and "slow enough" shutter speed at minimum ISO, but no more than that.

Yeah I see what you mean. The more I "stretch" the camera's  capabilities with filters, the worse the picture could be. But what I was thinking would work, say, in sunny area where I want to get the flow of water, would be to use a ND or my polarizer  to cut down the light after I am at closed Fstop, which is F8 for the camera. F8 isn't much it seems when you are in bright light and you have a possible shutter speed of 30 seconds. So I would use:
ISO 64
F8
ND or my polarizer to cut down on the light, depending on intensity, helping the paltry F8 maximum setting. Does that sound like I'm thinking in the right direction?

Also, I now understand waht youar e saying about my maximum setting--F2.2. If I am at 2.2 an ND won't help me any becsaue that is the cameras limit. Problem is that in sunny days I couldn't use that setting to get a nice blurred background because the picture would be overexposed. It seems wiht my polarizer it allows the camera to use a much lower F setting, which gives a shallower DoF--this sound right?

[Jonathan Wienke]

Also, I now understand waht youar e saying about my maximum setting--F2.2. If I am at 2.2 an ND won't help me any becsaue that is the cameras limit. Problem is that in sunny days I couldn't use that setting to get a nice blurred background because the picture would be overexposed. It seems wiht my polarizer it allows the camera to use a much lower F setting, which gives a shallower DoF--this sound right?

Yes. ND, polarizer, or a combination of both until you get to f/2.2 and a slow enough shutter speed at ISO 64, then leave well enough alone.